1. Field of the Invention
The present invention relates to a micro-sized needle which is insertable through a patient's dermal layer for sampling of tissue in vivo. More specifically, the present invention relates to a needle having a micrometer internal diameter through which a plurality of sensing probes and delivery tubules are extended for monitoring cell parameters at the needle distal end and for delivering therapeutic fluids directly into tissue cells.
2. Description of the Related Art
Prior medical procedures for delivery of therapeutic fluids to treat systemic diseases include utilizing a hypodermic needle for delivery of mixtures of medication by means of an intravenous (IV) drip into a patient's vein. If the disease is diagnosed early and is localized in one organ or a group of cells within a patient, then systemic distribution of the medication within the patient by the arteries and veins is not efficient when compared to delivery of medication by hypodermic needle inserted proximal of the diseased cells. Typical hypodermic needles utilized in prior medical procedures include needles having an outer diameter (OD) of approximately 300 micrometers, and having an internal diameter (ID) of approximately 150 micrometers. One type of a medication infusion system is illustrated in U.S. Pat. No. 4,191,184 (the '184 patent), issued to J. A. Carlisle. The infusion regulation system of the '184 patent provides for regulating, monitoring, and control of IV infusion of fluids in a patient. The infusion regulation system provides a volume control apparatus including a peristaltic pump unit providing fluid flow through divaricated tubing for delivery of measured volumes of fluids to an outlet tube attached to a cannula inserted in a patient's vein. The system of the '184 patent provides for systemic infusion of a relatively large volume of pre-mixed fluid and lacks the ability to deliver one or more therapeutic fluids in precise volumes to a tumor or numerous groups of diseased cells.
Prior medical procedures for positioning of probes by means of an incision into a patient includes insertion of optic fibers in a patient to view a tumor, or insertion of surgical instruments to excise a tumor. One example includes a surgical instrument inserted through a sleeve member positioned in an incision proximal of a joint member as illustrated in U.S. Pat. No. 4,461,281 (the '281 patent), issued to R. W. Carson. The arthroscopic surgical apparatus of the '281 patent includes a hollow cannula having an ID of about 5 mm for insertion therein of a blade shaped tip of an elongated shaft. The cannula provides a tubular guide to position the blade shaped tip in a knee joint and to facilitate penetration by the blade shaped tip through the subcutaneous tissue and fascia of the knee joint during joint tissue repair. Additional cutting tools or optic fibers are utilized by inserting through a second cannula positioned proximal of the knee joint and adjacent to first cannula, or the blade shaped tip of the elongated shaft is removed from first cannula followed by insertion of a second cutting tool or an optic fiber for viewing the joint tissue repair. The apparatus of the '281 patent does not provide for one needle which remains positioned in an incision during a surgical procedure, with one needle having multiple channels therein for positioning of optic fibers for viewing while concurrently positioning one or more treatment instruments against the joint tissue undergoing repair.
Recent medical procedures utilizing probes inserted into a patient's organs includes positioning of laser probes for eye surgery as illustrated in U.S. Pat. No. 5,643,250 (the '250 patent), issued to F. E. O'Donnell, Jr., and in U.S. Pat. No. 6,520,955 (the '955 patent), issued to M. Reynard. The '250 patent illustrates a laser probe which includes a fiber optic channel and an infusion port for irrigating solutions to be infused into an eye during laser surgery on cornea tissue. The laser probe is manipulated as a hand piece for insertion of the probe tip through the cornea of a patient's eye, in order to position the probe tip having a fiber optic opening therein in close proximity to the target cataract tissue. The laser probe diameter may not allow insertion through numerous layers and densities of tissues disposed between a dermal surface and internal organs disposed medially within a patient. The '955 patent illustrates a process and apparatus for removing cataract tissue in an eye and for injecting a lens replacement material into the eye lens to fill the intralenticular space. The apparatus of the '955 patent includes a needle having dual cannula oriented as coaxial annular conduits through which chemicals and enzymes are delivered into cataract tissue. A separate focused laser is utilized to destroy the cataract tissue, followed by destroyed cataract tissue being removed by aspiration through an aspiration instrument or through a coaxial annular conduit of the needle. The diameter and configuration of the dual cannula needle may limit precise insertion into a specific tumor in an organ after needle insertion through multiple layers and tissue densities within the patient.
A need exists for a minimally intrusive microneedle which is positionable into a cell or a group of cells, and is capable of actively retrieving samples for monitoring of current cell conditions while remaining inserted in the cell or group of cells. There is a further need for a microneedle having a plurality of microtubules providing channels for optic fibers, channels for samples intracellular conditions, and channels for delivery of therapeutic fluids into the cell in order to promote healing of, or selective suppression of specific cells.